High speed printer with reciprocable type bar



Oct. 19,1965 J. H. WALKER 3,212,435

HIGH SPEED PRINTER WITH REGIPROCABLE TYPE BAR Filed July 1, 1963 6 Sheets-Sheet 1 INVENTOR JAMES HAROLD WALKER ATTORNEY Oct. 19, 1965 J. H. WALKER 3,212,435

HIGH SPEED PRINTER WITH RECIPROGABLE TYPE BAR Filed July 1, 1963 6 Sheets-Sheet 3 OPTTB ADV2 Oct. 19,

Filed July 1, 1963 1965 J. H. WALKER 3,212,435

HIGH SPEED PRINTER WITH RECIPROCABLE TYPE BAR 6 Sheets-Sheet 4 PULSE A rfi r":

PULSE 0 1-: F1 r1 PULSE 0 |1 [*1 J l 0m 1 1 L ADDRESS I 000 U 001 LP 002 L1 Pcc ADVANCE PULSE 1 F1 J I l l COMPARE EQUAL F"! 1 1 PRINT MAGNE'T 000 I PRINT MAGNET 001 l PRINT MAGNET 002 FIG. 6

0 I u l -v u 13 2 I ea J. H. WALKER 3,212,435

HIGH SPEED PRINTER WITH RECIPROGABLE TYPE BAR Oct. 19, 1965 6 Sheets-Sheet 5 Filed July 1, 1963 4m QE 223;:

mdE I m m m m m m m m m P z o m z I Q m Q q HIGH SPEED PRINTER WITH RECIPROCABLE TYPE BAR Filed July 1, 1963 J. H. WALKER Oct. 19, 1965 6 Sheets-Sheet 6 POO 1 POO NOT 1 OO NOT 2 OO 4 POO NOT 4 POO 8 POO NOT8 POO D POO NOT D POO 1 POO 4 POO NOT1 POO NOTA TB 13 POO ADV PU-SE POO TS' POO NOT 1 FIG.

United States Patent Office 3,212,435 Patented Oct. 19, 1965 national Business Machines Corporation, New York,

N .Y., a corporation of New York Filed July 1, 1963, Ser. No. 292,041 8 Claims. (Cl. 101--93) This invention relates to a high speed printing system in which a line is printed as a type carrier is horizontally displaced along the print line and, more particularly, to a code generating means which indicates the type character at a predetermined position.

In an incremental bar printer, a type bar having all the characters of the alphabet is driven with a start-and-stop motion in steps horizontally across the print medium. At each step printing takes place as hammers are released for all characters in which the position of the character on the type bar corresponds to the desired print data for that position. At the end of the printing line the type bar motion is reversed, and the machine then prints the next line as the type bar steps in the opposite direction. Due to the varying requirements of users, a plurality of interchangeable type bars having different numbers and arrangements of discrete characters comprising the alphabet are provided. While prior art printing systems have character code generating means suitable for use with a single type bar alphabet, none is suitable for use in a printing system in which printing takes place in both directions of type bar movement and which is capable of selectively employing one of a plurality of different type bars.

It is a primary object of this invention to provide control means for determining the specific character on the type bar that is aligned for printing in a given print position.

It is another object of this invention to provide means for sequentially comparing the character on the type bar that is aligned for printing in a particular position with the character in storage to be printed at that position for each step of the type carrier.

It is a further object of this invention to provide means for determining at which time print hammers should be released to print a character at a predetermined print position.

It is a still further object of this invention to provide means for detecting the specific character on the type carrier that is aligned for printing in a print position without regard to the direction of movement of the type carrier.

It is a further object of this invention to provide counting means for generating coded signals representing the character on the type bar, wherein the counting means is stepped responsive to type bar direction sensing means and to selective means for determining the one of a plurality of type bars being used.

According to the invention, a high speed printing system is provided having a character code generating means for generating coded representations of the type characters, and means for controlling the stepping of the character code generating means in a predetermined manner responsive to type bar direction sensing means and to type bar selectionmeans so that a code is generated representing the type bar character in synchronism with the actuating means being addressed for printing comparison.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.

FIG. 1 is a diagrammatic schematic view of a printing mechanism according to the invention.

FIG. 2 is a diagrammatic cross section of a printer according to the invention.

FIG. 3 is a schematic view of the type 'ba-r drive mechanism of the printer of FIG. 2.

FIG. 4 is a schematic block diagram of the electronic control circuitry for the printer embodying the invention.

FIG. 5 is a schematic block diagram of the electronic control circuitry for the print character counter.

FIG. 6 shows the timing relationship between various control pulses for the electronic control circuitry of the printer.

FIG. 7 shows a typical circuit for the solar cell sensing means.

FIG. 8 shows the 6-digit binary code chosen to represent the characters which may be printed.

FIG. 9a shows the character arrangement for the 13- character type bar.

FIG. 9b shows the character arrangement for the 52- character type bar.

FIG. shows the character arrangement for the 63- character type bar.

FIG. 10 is a schematic block diagram of the gated counter portion of the print character counter.

FIG. 11 is a schematic block diagram of the binary counter portion of the print character counter.

The printing means comprises a type bar 10, a type bar drive mechanism 12, and a printing means 14. The printing means also comprises a suitable print transducer 16 and a transducer restore mechanism 18. The type bar drive mechanism 12 functions to move the type bar with a start-and-stop motion in steps across the print medium 20. At each step of the type bar, printing takes place as printing transducers 16 are released. When released, printing transducers 16 move toward the right (FIG. 2), forcing the type face 22 against the ribbon 24, document 20 and platen 26 to accomplish printing. At the end of the printing line a sensing means 28 operatively associated with the type bar is energized, and an end-of-line signal thus generated is used to control the moving of the form by drive means 23, the restoring of the print transducer, and the reversal of the type bar motion. The next line is then printed as the type bar is stepped in the opposite direction by the bidirectional drive system 12.

Printing takes place at a particular position when the type bar character at that position is the same as the character in storage that is to be printed in that position. The information character to be printed is supplied by a source of information such as the processor of a data processing system, for example. The information characters may be utilized directly from the processor storage device or temporarily stored in a buffer memory. Since the butfered operation is more economical of processor time, this mode of operation is shown in FIG. 4. The buifer memory may comprise any suitable type of storage device, such as a magnetic core storage 43, for example.

In the printer shown, a line comprises characters, and the buffer memory is capable of storing information characters for one line of print. The characters to be printed may be represented in any suitable code such as, for example, the binary coded decimal system comprising the six character bits 1, 2, 4, 8, A and B. The binary coded decimal code chosen for the characters is shown in FIG. 8.

An addressing means 55, 57 is provided which controls read-out of print characters serially from print position one to print position 150, and the corresponding print transducer is simultaneously addressed. A code generating means 45 is provided which generates the binary coded signals representing the characters as they appear on the type bar being used.

The character generating means and the storage scan are started at the same time by a print control means 53' which is controlled by a motion sensing device on the type bar drive. Character code generating means 45 is reset to generate a certain character, depending on the type bar being used so that at the first address step the character code corresponds to the character then at print position one. The character to be printed and the generated code are routed to compare circuit 69 for each print position, and a signal energizes the print transducer on an equal compare. The operation continues in this way with the code generator being stepped in synchronism with the print transducer addressing to generate, in binary bits, the character on the type bar which is in front of each print hammer at the time the print magnet for that hammer is addressed. The print character counter generates serially a character for each of the print positions of the printer so the counter completes more than one cycle for each print line. The type bar is then incremented to a new position, thereby positioning different characters in front of the print transducers.

A bidirectional drive system 12 (FIG. 3) is provided for movement of the type bar. The system is driven by a motor 34 which drives two counter-rotating clutch shafts 36, 38. A right and a left 32 drive clutch are provided, and the particular clutch is energized or de-energized by a type bar control circuit (FIG. 4) so that the appropriate clutch turns shaft 41 in the desired direction. An incremental motion device 44 is mounted between input shaft 41 and output shaft 42 to produce an intermittent or stepping motion of output shaft 42. A pinion gear 46 is mounted on the output shaft and drives the type bar. A motion sensing device comprising a magnetic emitter timing wheel 48 is mounted on the input shaft, and this emitter provides a pulse for each step of the type bar, which is used to time the start of the storage scans.

A continuously driven type bar may be used by eliminating the incremental motion device 44 and adjusting the motion sensing device to generate proper synchronizing pulses to start each storage scan. The storage scan and the comparison are performed at electronic speed, and the action of the print transducer is rapid enough to prevent appreciable blurring of the printed characters due to the continuous motion of the type bar.

A magnetic brake 47 is mounted on the clutched shaft 50 which drives the input shaft 41, and this brake is energized when the end of the print line is recognized by the line-start solar cell to provide a positive step for the input shaft 41 rotation so that the appropriate type ba-r clutch, when energized, may start moving the type bar in the opposite direction for the next line of print.

A plurality of type bars are provided, and an example of the alphabet for three type bars is shown in FIG. 9. An optional numeric type bar having 13 characters is shown in FIG. 9a, and the standard SZ-character type bar is shown in FIG. 9b. The optional 63-character type bar is shown in FIG. 90. The type bar is easily replaceable, and each type bar comprises enough segments of the alphabet to extend over all print positions, plus one additional segment containing all the characters of the alphabet since printing occurs in both directions of type bar movement. The type bar being used is communicated to the control circuitry by means of a settable type bar selection switch (TBS) which is mounted on the printer control panel.

The sensing means 28 comprises a type bar flag portion 59 which cooperates with four sensing devices such as solar cells and lamps 61, 63, 65 and 67 which are mounted adjacent to the right end (FIG. 1) of the type bar assembly. The type bar flag 59 is mounted on the right end of the type bar and passes through the solar cell light beam as the type bar is stepped and the output from the solar cells indicates the type bar position. The solar cell is connected in the base circuit of a transistor amplifier (FIG. 7). When the solar cell is exposed to a light beam, the cell generates enough current to cut off the collector current of transistor 73. When the light beam is broken, the solar cell stops conducting and the amplifier is driven into saturation. Therefore, the output of the amplifier 4 indicates when the light beam is unbroken or broken. The solar cells are used as a sen-sing means to determine whether the type bar is in the right or the left home position. When power is first turned on and the start key is depressed, the control circuits are designed to cause the movement of the type bar to the left home position if the type bar is not already in one of the two home positions. The type bar is in a home position when the line-start solar cell is exposed by type bar flag 59. If the direction solar cell 67 is also exposed to the light at this time, it signals the control circuits that the type bar is in the right home position. If direction solar cell 67 is covered, the direction solar cell signals that the type bar is in the left home position. The left type bar clutch 32 is energized when the type bar is in the right home position, and the right type bar clutch 30 is energized when the type bar is in the left home position. After a line print cycle is completed the hammer restore solar cell 61 is exposed, thereby producing a signal which energizes the restore clutch. When the line-start solar cell.65 is covered, this signals the control circuitry that a new line of print is ready to begin. When the line-stop solar cell 63 is then exposed, this signals the control circuitry that a line of printing has been completed.

A character code generating means 45 is used during the line print cycle to indicate the type bar character which is at the addressed print position. In the embodiment shown, the generator comprises two counters 51, 56. A numeric counter 56 comprises five bistable devices '58, 60, 62, 64, 66 coupled to count in binary fashion representing the binary signals 1, 2, 4, 8, D. A second counter, the A-B counter 51, comprises two bistable devices 52, 54 which are selectively gated according to the type bar being used. Under normal operation, the counters are coupled so that each time the A-B counter is advanced from the last step to the first step the numeric counter is advanced one step. The two counters together may be termed a print character counter (PCC). Since the type bar can be moved in either direction, and the circuits are designed to scan the information in the buffer memory always in the same direction, circuit means are provided to increment the character counter when the type bar is moving to the left and decrement the counter when the type bar is moving to the right. i

The basic timing for printing during the line print cycle is controlled by the processor in the unbulfered operation. Processor timing signals are gated to produce printer timing pulses A, B and C, respectively, in the buffered operation. At pulse A time the print character counter is advanced; at pulse B time the print character counter character and the processor storage character are compared, and. print hammers are released on equal compare; pulse C is a control pulse for resetting certain control circuitry.

The print character counter is reset to a predetermined position in preparation for a line print cycle, and this predetermined position is dependent upon the characters to be generated on the type bar being used. For example, when the 52 or the 63-character alphabet type bar is used, the P00 is reset to the cent sign. This action is accomplished by the signal PCC RST which is generated through OR circuit 98 when AND circuit '97 is conditioned. AND circuit 97 is conditioned when the run latch is set and hammer restore circuit breaker 3 (HR'CB 3) is closed. HRCB 3 signifies that the print hammers have been restored. The signal PCC RST conditions AND circuit 100 to generate the signal B RST OFF, and through OR circuit 101 the signal A RST ON. The signal A RST ON is coupled to the DC. set input of trigger 52 to produce the output PCC A. The signal B RST OFF is coupled to the DC. reset input of trigger 54 to produce the output PCC NOT B. The signal PCC RST also is coupled to the DC. reset input of each trigger of counter 56 to set those triggers off. Thus, there remains in the PCC the code for the cent-PCC A. When the 13-ch'aracter numeric type bar is being used, the PCC is reset to the dash sign (PCC B). The signal PCC RST is generated as above, and the signals B RST ON and A RST OFF are generated from AND circuit 103 and OR circuit 105.

A line print cycle is initiated by a signal from the processor which raises the print line in the printer and initiates the type bar motion. When the type bar flag covers the line-start solar cell 65, the signal PRINT GT comes up. This signal gates the next pulse originating at the type bar drive emitter to generate an output which sets the print cycle gate latch so that the print character counter advance latch 70 is turned on, and an advance pulse is generated when the proper type bar clutch is energized and an A pulse appears. When the type bar moves to the left, each succeeding type bar character at a particular position is one character past the previous character at that position. Since a character code must be generated for each of the 150 print positions, the PCC is advanced through its cycle three times for each storage scan. This means that during the last six steps no print magnets are being addressed, but the PCC cycle is completed to simplify the control circuitry. When the type bar is moving left, the first character which comes into print position is the ampersand at the first print position (print magnet address 000). Since the print character counter is reset to the cent sign at the start of the cycle, the PCC must be advanced once to contain an ampersand character.

The PCC advances are terminated by print magnet address 156 which turns off the PCC ADV latch 70 through AND circuit 71. After the completion of the storage scan on the first print dwell, the PCC has taken 157 advances and contains an ampersand code which is one character past the cent sign. This advancing sequence is repeated for each succeeding storage scan cycle, with the PCC always starting with an advance that brings it to the same character that is on the type bar opposite print position one.

The PCC advance control differs somewhat when the type bar is moving to the right. When the type bar is moving to the right, each succeeding print dwell represents a type bar character that precedes by one the previous character at the corresponding print position. Consider print magnet address 000 (print position 1). The type bar character at print position one is a cent on the first storage scan of a line print cycle. Since the PCC was reset to a cent character after the previous hammer restore cycle, an advance at print magnet address 000 is blocked. Because the type bar character at print position one on the next step is the colon, the PCC character at the start of the next storage scan must be a colon. This requires that the PCC advance only 155 times during the storage scan. Because the PCC normally advances 157 times during a storage scan, two advances must be blocked. One advance, as shown above, is blocked at 000. The second block occurs at address 150, which is after printing is completed at each print dwell. This blocking is accomplished by AND circuit 102 which is deconditioned by addresses 000 and 150 to block the generation of an advance pulse.

The A-B counter is gated to advance through a 4-step cycle which produces the following outputs in sequence: step 1, PCC NOT A and PCC NOT B; step 2, PCC A and PCC NOT B; step 3, PCC A and PCC B; step 4, PCC NOT A and PCC B. The advancement is under control of the signal ADV PULSE which is generated from OR circuit 68. The PCC advance latch 70 is set by the signal PR CY GT ON which is generated when the print cycle gate latch (not shown) is set, and this occurs at the start of each line print cycle. This output is combined with the signals PULSE A, PRINT GT in AND circuit 72. The output of AND circuit 72 is combined with a type bar direction signal in AND circuits 74, 76, depending on whether the type bar is moving right or left, respectively. The signals TB CL RT and TB GL LT are generated from a latch (not shown) which is set to one 6 state or the other, depending on the output from the position sensing solar cell.

Each time the A-B counter 51 is advanced from the fourth step to the first, the numeric counter 56 is advanced one step. This opration is controlled by AND circuit 78 which is conditioned on the fourth step of the A-B counter, and the output partially conditions AND circuit 80 through OR circuit 82. Since the counter was reset to PCC NOT 1, AND circuit 80 is fully-conditioned to produce an up-level to partially condition gate 84. The next advance pulse on line 86 then conditions gate 84 and sets trigger 58 to generate the output PCC 1.

When the standard SZ-character type bar is being used, a reset to the cent sign must occur during a line print cycle when the colon (PCC 8, PCC 4, PCC 1) is reached since the cent sign follows the colon in the standard alphabet. Since the PCC has the capacity to generate the 63-character alphabet, an equal sign (PCC A, PCC 8, PCC 4, PCC 1) would be generated. The PCC reset latch 88 is set by sensing the code for a colon which partially conditions AND circuit 90. At pulse C time, AND circuit 90 is fully conditioned, and the output is coupled to OR circuit 92 to set the PCC reset latch 88. The PCC reset latch output is combined with the next advance pulse in AND circuit 96 to produce through OR circuit 98 the output PCC RST. The PCC reset latch is turned off through OR circuit 94 at pulse B time and also on a reset machine operation.

The signal PCC RST is coupled to reset each of the triggers 5866 to the off condition. The signal PCC RST is also combined with the TBS 52 signal in AND circuit 100 to generate the signal B RST OFF which is used to turn trigger PCC B off. The signal is coupled to generate the signal A RST ON, and this signal is coupled to the set input of trigger PCC A. Thus, the counters contain PCC A, which is the code chosen for the cent sign.

Trigger 66, PCC D is required to generate the two blank characters before the cent sign in the 63-character alphabet. The signal PCC D is generated when PCC 8 goes off and A-B counter 51 goes from its fourth step to its first step. The signal PCC D is coupled to block the compare circuit to prevent printing. On the next advance of the PCC, PCC A comes on along with PCC D. At pulse C time the PCC RST latch is set through AND circuits 104, 108 and OR circuit 106. The next advance pulse then resets the PCC to the cent sign, so this places the PCC at the correct character at the correct time.

The bistable devices comprising counters 51, 56 may be of any suitable type. The triggers shown in the drawings comprise a DO. set and a DC. reset input which takes precedence over the gated inputs. The diamond shaped input to the gates represents a DC. level input or DC. gate, and the bottom input (FIG. 10) comprises an AC. set input. The simultaneous presence of these inputs produces an output which sets the coupled side of the trigger on.

While the invention has been particularly shown and desquibed with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that the foregoing and other changes in the form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. In a high speed line printer:

a type carrier;

a plurality of print transducers;

means for driving the type carrier in either direction across a printing surface;

means for storing coded data representing the characters to be printed;

means for sensing the direction of movement of said type carrier;

means for generating coded data representing the characters on said type carrier;

addressing means for sequentially addressing positions of said storage means and said print transducers; and

means under control of said direction sensing means for stepping the character generating means fewer times than said addressing means in one direction of movement of said type carrier and a greater number of times than said addressing means in the opposite direction of movement of said type carrier for generating coded data according to the character at a predetermined position.

2. In a high speed printing apparatus:

type carrier means;

a plurality of print transducers;

means for moving the type carrier means in either direction across a printing surface;

means for storing coded data representing characters to be printed;

means for generating coded data representing the characters on said type carrier;

means for sensing the direction of movement of said type carrier;

means under control of said direction sensing means for sequentially stepping the code generating means to generate said coded data in accordance with the position of the characters on said type carrier;

means for sequentially comparing said stored information and said generated character codes; and

means under control of a compare signal to energize the corresponding print transducer so that the desired character is printed upon the printing surface.

3. In a high speed printing apparatus:

a plurality of type carrier means;

means settable for selecting a particular type carrier;

means for moving the type carrier means in either direction across a printing surface;

a plurality of printtransducers;

means for storing coded data representing characters to be printed;

means for generating coded data representing the characters on said type carrier;

addressing means for sequentially addressing positions of said storage means and said print transducers;

means for sensing the direction of movement of said type carrier;

means under control of said direction sensing means for sequentially stepping the code generating means to generate said coded data in accordance with the type character at the addressed position;

means for comparing said stored information and said generated character codes; and

means under control of a compare signal to energize the corresponding print transducer so that the desired character is printed upon the printing surface.

4. In a high speed line printer:

a type carrier;

a plurality of print transducers;

means for driving the type carrier in either direction across a printing surface;

means for storing coded data representing the characters to be printed;

a character counter for generating coded data representing the characters on said type carrier;

addressing means for sequentially addressing positions of said storage means and said print transducers;

means for sensing the direction of movement of said type carrier;

means under control of said direction sensing means for stepping the character counter in one direction or the other relative to said addressing means according to the direction of movement of said type carrier for generating coded data according to the character at a predetermined position;

means for sequentially comparing the stored data characters with the coded data for each character on the type carrier for each step of the type carrier across the printing surface; and

means responsive to a compare signal for energizing a printing transducer to print the selected character at thepredetermined position in the print line.

5. In a high speed printing apparatus:

a plurality of type carrier means;

means settable for selecting a particular type carrier means;

means for moving the type carrier means in either direction across a printing surface;

means for storing coded data representing characters to be printed;

means for sensing the direction of movement of said type carrier;

means for generating coded data representing the characters on said type bar;

said coded data generating means comprising a first and a second countingmeans;

means for coupling said counting means so that a complete cycle of said first counter causes said second counter to advance one step; and

means under control of said direction sensing means and said settable means for selectively altering said coupling means so that said code generating means generates coded data in accordance with the alphabet on said selected type carrier.

6. In a high speed line printer:

a type carrier;

a plurality of print transducers;

means for driving the type carrier in either direction across a printing surface;

means for storing coded data representing the characters tobe printed;

means for sensing the direction of movement of said type carrier;

means for generating coded data representing the characters on said type carrier;

addressing means for sequentially addressing positions of said storage means and said print transducers;

means under control of said direction sensing means for stepping the character generating means fewer times than said addressing means in one direction of movement of said type carrier and a greater number of times than said addressing means in the opposite direction of movement of said type carrier for generating coded data according to the character on the type carrier at a predetermined position;

means for sequentially comparing the stored data characters with the coded data for each character on the type carrier for each step of the type carrier across the printing surface; and

means responsive to a compare signal for energizing a printing transducer to print the selected character at the predetermined position in the print line.

7. In a high speed printing apparatus:

a plurality of type carrier means;

means settable for selecting a particular type carrier means;

means for moving the type carrier means in either direction across a printing surface;

means for storing coded data representing characters to be printed;

means for sensing the direction of movement of said type carrier;

means for generating advancing signals;

means for generating coded data representing the characters on said type bar;

saidcoded data generating means comprising a first and a second counting means;

means for coupling said second counting means to count in a binary fashion in response to said advancing pulses; and

means under control of said direction sensing means and said settable means for selectively gating said advancing pulses to said first counting means so that said code generating means generate coded data in accordance with the alphabet on said selected type carrier.

8. In a high speed printing apparatus:

a plurality of type carrier means;

means settable for selecting a particular type carrier means;

means for moving the type carrier means in either direction across a printing surface;

means tor storing coded data representing characters to be printed;

means for sensing the direction of movement of said type carrier;

means for generating advancing signals;

means for generating coded data representing the characters on said type bar;

said coded data generating means comprising a first and a second counting means;

means for coupling said counting means so that a complete cycle of said first counter causes said second counter to advance one step; and

means under control of said direction sensing means and said settable means for selectively gating said advancing pulses to said first counting means so that said code generating means generates coded data in accordance with the alphabet on said selected type carrier.

References Cited by the Examiner UNITED STATES PATENTS 2,831,424 4/58 MacDonald 10193 2,911,085 11/59 Leathers 1971 2,936,704 5/60 Hense 10193 2,997,152 8/61 Dirks 197-1 3,135,195 6/64 Potter 101-93 WILLIAM B. PENN, Primary Examiner. 

1. IN A HIHG SPEED LINE PRINTER: A TYPE CARRIER; A PLURALITY OF PRINT TRANSDUCERS; MEANS FOR DRIVING THE TYPE CARRIER IN EITHER DIRECTION ACROSS A PRINTING SURFACE; MEANS FOR STORING CODED DATA REPRESENTING THE CHARACTERS TO BE PRINTED; MEANS FOR SENSING THE DIRECTION OF MOVEMENT OF SAID TYPE CARRIER; MEANS FOR GENERATING CODED DATA REPRESENTING THE CHARACTERS ON SAID TYPE CARRIER; ADDRESSING MEANS FOR SEQUENTIALLY ADDRESSING POSITIONS OF SAID STORAGE MEANS AND SAID PRINT TRANSDUCERS; AND MEANS UNDER CONTROL OF SAID DIRECTION SENSING MEANS FOR STEPPING THE CHARACTER GENERATING MEANS FEWER TIMES THAN SAID ADDRESSING MEANS IN ONE DIRECTION OF MOVEMENT OF SAID TYPE CARRIER AND A GREATER NUMBER OF TIMES THAN SAID ADDRESSING MEANS IN THE OPPOSITE DIRECTION OF MOVEMENT OF AID TYPE THE OPPOSITE GENERATING CODED DATA ACCORDING TO THE CHARACTER AT A PREDETERMINED POSITION. 